There is increasing interest in electronic sensors for detecting chemical and biological agents, analytes, or reaction byproducts. Furthermore, there is a push to develop sensors with greater sensitivity, capable of detecting ever smaller changes in concentration or solution pH. There is also a move to decrease reaction volumes, particularly when detecting the byproducts of reactions.
In one exemplary system, pH-based sequencing of biomolecules, such as nucleic acids or proteins, utilizes small changes in pH in reaction volumes on the order of nanoliters or smaller. For example, target nucleic acids can be disposed in volumes of less than a nanoliter and nucleotide incorporation along the target nucleic acids can be detected based on small changes in pH resulting from the nucleotide incorporation.
The reliability of such sensitive sensors can be influenced by both the stability of the sensor devices and the consistency of the sensor calibration. Such stability and consistent calibration can be affected by packaging, storage, and transportation.